Any thoughts where i can get one of these?

[73GMC10]

I bought a 73 gmc 3/4 ton and it has 15x10 3.5 inch Bs white spoke rims on it and I need to replace one of the rims as the lug holes are totally trashed and the owner put washers on them and then the nut from moving around over time I seen every lug is about 75% wore through wich thankfully didn't snap off while I was driving, anyone know where I could find one of these? summit racing doesn't have them in 3.5 and locally cant get them( Saskatchewan,Canada)